The State of in Report 2020 Headlines

40 % of Swiss breeding birds are threat- ened, among them many farmland spe- cies. Their population trend remains low, with still no signs of recovery. Not a single Grey Partridge was recorded in 2019.  page 6

Wetlands are biodiversity hotspots, and home to many specialised . But populations remain small and unable to make up for earlier losses.  page 7

Populations of woodland birds are increasing. But there are exceptions: the Boreal Owl has declined steeply in the Jura. New methods will improve the monitoring of its population in the Alps as well.  page 8

Some bird species fare well in landscapes radically changed by humans, among them and Red Kite. Specific conser- vation measures can help the Eurasian Jackdaw.  page 10, 22

2 The lakes and rivers of Switzerland at- tract some 500 000 wintering waterbirds. Due to climate change, more and more winter visitors, for example Mallards, winter further northeast.  page 24

Numbers of mountain birds have dropped by 10 % in Europe since 2002 as a result of climate change and intensified land use. Declines are less marked in the Alps, un- derscoring Switzerland’s responsibility in the protection of these birds.  page 30

The second European Breeding Bird Atlas will be published at the end of the year. It reveals massive range changes for breeding birds. For example, the breed- ing range of the Reed Bunting in south- ern Europe has shrunk significantly since the 1980s.  page 32

Contents Editorial ...... 4 Breeding birds ...... 6 Migrants ...... 16 Methodology ...... 20 Winter visitors ...... 22 Further information International news ...... 30 You can find further information online, in- cluding population trends for breeding birds Acknowledgements ...... 34 and additional analyses: www.vogelwarte.ch/state Authors and copyright...... 35

3 EDITORIAL

Bird monitoring in the Swiss cantons

The Red-backed Shrike, bird of the year confident that the new agricultural pol- 2020, is a fascinating creature. It is easi- icy is truly taking effect. ly recognised in the , and you don’t But the example of the Red-backed have to be an ornithologist to under- Shrike highlights the fundamental im- stand its fate. portance of species monitoring; it is the The steep decline in the population only way to document population de- in the past decades is a result of inten- clines, but also the effect of measures sified farming practices, especially the taken in the field. It may sound easy. loss of hedges and bushes in farmland But in fact, biodiversity management as well as the use of fertiliser and pes- is highly complex: we are faced with a ticides in meadows and field margins. diverse range of habitats, many species To reverse the trend for this insecti- with different ecological requirements, vore, we need to improve habitat qual- a complicated web of interactions be- ity and food supply, that means plant- tween ecosystems and all kinds of hu- ing hedges, reintroducing structur- man influences. In addition, the issue al features in agricultural landscapes, of biodiversity involves diverging pub- and massively reducing the use of lic interests. Conservation legislation is these are some first encouraging signs pesticides! an important part of the solution, but of success for everyone involved in im- The slight increase in the nation- it is not enough. plementing and overseeing our conser- al breeding bird index for the Red- In the highly complex world we live vation goals. backed Shrike is probably due to lo- in, the cantons and other levels of ad- The of decided on cal measures to promote biodiversity ministration are extremely lucky to a new action plan for biodiversity in as well as favourable weather condi- have at their disposal a resource like 2019. In to document the devel- tions. Let’s hope that it also reflects the the common breeding bird monitor- opment of biological diversity at the new course in our national agricultur- ing scheme (Monitoring Häufige Brut- cantonal level, we will mainly rely on al policy that aims to improve the sit- vögel, MHB), where fieldwork has been resources such as MHB. uation. The steps taken include a so- conducted annually for 20 years. Af- We are therefore extremely grate- called proof of ecological performance ter all, as administrators, we are not ful for the valuable work you do year introduced in 1999, and biodiversity only responsible for implementing le- after year. promotion areas introduced in 2012. gal provisions, but also have to check Much remains to be done, however, their effectiveness. and the recovery of the Red-backed When monitoring data indicate that Dr Cornelis Neet Shrike has barely just begun. We need a population trend is stabilising even General director for the environment to see long-term positive reactions in reversing, such as currently appears to in the Canton of Vaud a range of species before we can be be the case for the Red-backed Shrike,

The common breeding bird monitoring scheme (MHB) shows that the population of the Red-backed Shrike has stabilised or may even be increasing slightly, following a decline that halved the population in the last 30 years.

4 Not all breeding bird species are sufficiently covered by MHB, for example the Grey-faced Woodpecker. But by combining monitoring data with other data, we can nevertheless effectively document its population trend. A Grey Partridge : images like this one may be a thing of the past in Switzerland.

Grey Partridge: another farmland bird has disappeared

Unfortunately, it looks like 2019 will was the first step and took place in the a few square kilometres) and high enter the ornithological history of Klettgau and Champagne genevoise predator density. As a short-lived spe- Switzerland as the year the Grey Par- in close collaboration with farmers cies, the Grey Partridge needs suitable tridge disappeared. After two breed- and cantonal authorities. Large areas habitats in a catchment area far larger ing pairs were recorded in the Can- were ecologically improved with wild- than the size of the project areas. On ton of Geneva in 2018, there was not flower plots, low hedges and mead- the upside, other species such as Eur- a single observation of wild birds in ows managed at low intensity. Start- asian Skylark, Common Whitethroat 2019. This marks a sad low point for ing in 1998, the first Grey Partridges and Corn Bunting benefited greatly what was once a common farmland were reintroduced in the Klettgau, re- from the habitat improvements. bird. It is unlikely that the species will sulting in a population of 15–20 pairs return. from 2002 to 2004. After the pop- ulation collapsed, mainly due to ad- An iconic species disappears verse weather conditions, reintroduc- 600 In the mid-20th century, the Grey Par- tions in the Klettgau were stopped in 500 tridge population in farmland areas in 2008. The species was last observed 400 Switzerland was estimated at about there in 2016. 10 000 individuals. How large must the Model calculations indicated that 300 Index population have been in even earlier larger releases were necessary to sup- 200 times, for example around 1900, when port this short-lived species. From breeding pairs were found in Grisons 2008 to 2012, an average of 500 Grey 100 at up to 1300 m asl? In the second half Partridges were released in the Cham- 0 of the 20th century, the population pagne genevoise every autumn. Con- 1990 1995 2000 2005 2010 2015 rapidly collapsed. In 1991, the Feder- sequently, the breeding population in- al Office for the Environment (FOEN) creased to 60 pairs in 2012. But it was The breeding bird index for the Grey Par- tridge from 1990 onwards: the peaks in asked the Swiss Ornithological Insti- unable to sustain itself. The reasons for the mid-2000s and early 2010s reflect tute to carry out a recovery project for the failure are thought to be the insuf- the releases in the Klettgau SH and the the Grey Partridge. Restoring habitats ficient size of the project areas («only» Champagne genevoise.

6 BREEDING BIRDS

180 Meadow Pipit 160 White Wagtail 140

120

Index 100

80

60

40 1990 1995 2000 2005 2010 2015 Meadow Pipit and White Wagtail: trends are negative, to a greater or lesser extent, in these two species reliant on farmland areas.

In bad company as Corn Bunting, Whinchat, Northern The Grey Partridge joins a list of oth- and others to continue to ex- er farmland birds that were unable to ist in Switzerland. sustain their populations in Switzer- A look across the border only con- land. Lesser Grey Shrike, Crested Lark, firms that there is reason to fear the Great Grey Shrike, Woodchat Shrike, worst for the Grey Partridge. In Ger- Ortolan Bunting and now the Grey many, its numbers declined by 90 % Partridge are victims of the impover- from 1992 to 2016. Similarly, pop- ishment of farmland and food sourc- ulations have collapsed throughout Further information es. We must redouble our efforts as a Europe. www.vogelwarte.ch/state/breeding society if we want farmland birds such

The situation of breeding birds in 2019 2019 was the fifth warmest year since records began in 1864. Winter was average in lowland areas and much too warm in Ticino. The coldest January for more than 30 years was recorded in the mountains above 1000 m. The eastern ranges of the Alps in particular had a lot of snow. Snowfall was at re- cord highs again in April, and snow cover in the Alps stayed at winter levels due to unusually cool weather in May. The late snowmelt caused the decline recorded in many Alpine bird species in 2018 to continue in 2019. The month of May was exceptionally wet and cool in lowland areas and the Jura as well, so that finding time to conduct surveys besides their reg- ular job became a logistical challenge for many of our volunteers. The summer season was the third warmest since records began. Many birds faced difficult breeding conditions in particular because of the wet and cold weather in May. As in 2018, late breeders benefited from the warm and dry weather that followed.

140

120

100 Index 80

60 In 2019 the populations of many woodland birds (green) recovered Alpine habitats Woodland Wetlands from the previous year’s setback caused by the cold and snowy winter 40 2017/18. Alpine species (grey) declined because of the late snowmelt, 1990 1995 2000 2005 2010 2015 as in 2018. Wetland species (blue) showed an average trend in 2019.

7 BREEDING BIRDS

Locally, the Boreal Owl population is subject to large annual fluctuations owing to changing food supplies. Forestry interventions can affect Boreal Owl populations when old stands or trees with cavities are felled.

Owls: better monitoring thanks to new technology

Because owls are nocturnal, monitor- several species are currently very dy- of moderately common species that ing their populations requires special namic in Switzerland. breed in remote areas. In Switzerland, efforts. But it is all the more impor- As is often the case, the biggest such species include the Eurasian Pyg- tant because the population trends of challenges arise in the monitoring my-owl, the Boreal Owl and to a lesser extent the Eurasian -owl. Two of these nocturnal raptors

Unoccupied showed a substantial range expan- 1993–1996 sion in the period between the two 1993–1996 & 2013–2016 breeding bird atlases. In the Jura, the 2013–2016 Pygmy-owl has reached the Canton 2017–2019 of Neuchâtel and continues to spread northeastwards, occasionally breeding at lower altitude in northern Switzer- land. Populations of the Eagle-owl, on the other hand, have increased in den- sity in some regions of the Jura and the Alps as well as reoccupying some parts of the Central Plateau.

Decline of Boreal Owl popula- tions in the Jura The differences in monitoring quality may be even larger in the case of the The range expansion of the Eurasian Pygmy-owl between the 1993–1996 and 2013–2016 Boreal Owl than in the other two spe- breeding bird atlases has continued. cies, because its populations have been

8 BREEDING BIRDS

closely monitored for a long time in 60 the Jura, but only poorly in the Alps. Nest boxes Assessing the situation of the Boreal Tree cavities Owl for the whole of Switzerland is fur- 50 ther complicated by the fact that trends in the two regions appear to diverge: while declines are evident in the Jura, 40 the situation in the Alps seems to be more or less stable. These findings call for better popu- 30 lation monitoring across the board. On the one hand, we hope to benefit from bioacoustic tools; on the other hand, 20 we want to try drawing as much infor- records Number of breeding mation as possible from the data col- lected by volunteer field ornithologists. 10 Several studies on the use of bioacous- tics in owl monitoring are in progress: a Bachelor thesis on Boreal Owl and Eur- 0 1985 1990 1995 2000 2005 2010 2015 asian Pygmy-owl in the Jura and the Pre-Alps, a long-term Eagle-owl - The population trend of the Boreal Owl in the north of the Canton of Vaud, monitored itoring project in Ticino and Grisons since 1985 by Pierre-Alain Ravussin and his team, illustrates the species’ negative trend (focused on the Engadine), and a pilot in the whole of the Jura. 2011, 2013, 2018 and 2019 were the four weakest years since project on the acoustic detection of all the study began. Red = breeding in tree cavities, green = breeding in nest boxes. Source: Groupe ornithologique de Baulmes et environs. owl species in the Locarnese region in Ticino led by the Museo cantonale di storia naturale di Lugano. territory was missed in 71 % of the Eurasian Eagle-owl: easy to miss cases; of the territories occupied by despite its size pairs, 20 % went undetected and Of all three owls mentioned here, the 41 % were considered territories of Eurasian Eagle-owl is the best-mon- single birds; this means that the pres- itored species; but even here, our ence of a pair was recognised in only knowledge is incomplete. Monitoring 39 % of all cases. The results under- Eagle-owls involves several challenges: score the necessity to combine care- not all territories (not even all known ful fieldwork by our volunteers with territories) are visited every year, occu- modern acoustic loggers and sophisti- pied territories can be missed during a cated methods of analysis in the mon- survey visit, and a territory of a pair can itoring of these secretive and noctur- be erroneously classified as occupied by nal species. an individual bird only. Recently we have been able to ap- ply new methods to correct for these influences. We place automatic re- 120 cording devices (acoustic loggers) in known or suspected territories and an- alyse the data from ornitho using so- 110 called multistate site occupancy mod- els. Between 2007 and 2016, 19 % of The countrywide population trend 274 «paper territories» were unoccu- 100

of the Boreal Index pied, while 28 % were occupied by in- Owl appears to dividuals and 54 % by pairs, resulting be slightly nega- in a total of about 220 occupied ter- tive in the long 90 ritories. In most regions, trends were term, but the data used may stable or increasing, which is proba- incompletely bly due to immigration from Germa- represent the 80 ny and . Per visit, an individual’s situation. 1990 1995 2000 2005 2010 2015

9 BREEDING BIRDS

Rooks continue to expand their range

Rooks spread widely in France in 1963–1980 the 1950s and probably colonised 1981–1990 1991–2000 Switzerland from there. Breeding was 2001–2010 first recorded in the Plain VD in 2011–2019 1963. The Grosses Moos was occupied from 1964, and in 1965 the first pairs arrived in Basel. The population remained small until the late 1970s, not exceeding 100 pairs until 1983. After that, the Rook slowly spread. It reached Grenchen SO in 1987, Bern and the Ajoie JU in 1988, and Gene- va in 1997. Thun BE and Lucerne were colonised in 1998. In the same year, numbers exceeded 1000 pairs for the first time. The population subsequently The change in the Rook’s range shows how quickly the species has spread in Switzerland increased rapidly, reaching 4545 pairs since 2001. in 2010. The Canton of Zurich (Thal- wil) was colonised in 2007. The first colonies in Schaffhausen and the Val- population has declined by almost season. Also, breeding colonies that ais (Sion) were found in 2010 and 40 % in the last 20 years due to se- were suddenly abandoned (e.g. in the 2014, respectively. The species even- vere persecution. After a marked in- Orbe Plain) may indicate an increase tually reached Lake Constance, set- crease until the end of the 20th century, in predation pressure (for example by tling in Romanshorn TG in 2014 and the Rook’s overall European trend has the growing Eagle-owl population). in Rorschach SG in 2016. The popula- since shown a slight decline. Besides Both factors could lead to an increase tion continued to rise steeply, achieving direct persecution, intensified farming in breeding colonies in residential ar- its current peak of 8000 pairs in 2019. practices in many parts of Europe are eas, causing conflicts with residents. The strong range expansion and also causing problems for the species. Such conflicts result in frequent and in- growth in numbers in Switzerland was It suffers, for example, from the dis- tentional disturbance at breeding and probably, at least in the beginning, a appearance of low-intensity pastures, roosting sites. Hopefully, it will be pos- result of the Birds Directive adopted the massive use of pesticides, and the sible to improve the degree of toler- by the European Union in 1979, which chemical treatment of seeds. ance towards Rooks. placed all under protection. Rooks are being persecuted again In Germany the Rook population con- in Switzerland, too; since 2012, Rooks tinues to rise slightly, while the French can be hunted outside of the breeding

3500 Vaud, Fribourg, Neuchâtel 3000 Basel-Stadt, Basel-Landschaft, Jura Aargau, Solothurn, Bern, Lucerne 2500 City of Bern Geneva 2000 Zurich, Thurgau, St. Gallen Valais 1500 Number of pairs 1000

500

0 1979 1983 1987 1991 1995 1999 2003 2007 2011 2015 2019 As early as late January, the Rooks visit last year’s breeding colonies Population trends of the Rook in seven regions of Switzerland in the mornings, and March sees a burst in nesting and breeding (1979–2019). activity.

10 BREEDING BIRDS

Jackdaw: a small corvid regains momentum

The breeding population of Eurasian Fifteen years ago in the Bernese Jackdaws has risen by 40 % since the Seeland, Jackdaws occupied nest box- 1990s. This is the result of species re- es installed on power pylons for Com- covery projects as well as bird-friend- mon Kestrels, in proximity to abun- ly renovations and other measures to dant food sources. The occupation of encourage nesting on buildings. Like the site is probably related to the pres- other former cliff-nesting birds, Jack- ence of pastures, where ground-liv- daws have found a secondary hab- ing insects are easy to find in patches itat in settlements with historical of short grass. For several years now, buildings. nest boxes for Kestrels and Barn- owls in the plain near Oensingen SO The challenge of raising young in have been occupied by Jackdaws as large settlements well. Probable reasons are a shortage The gregarious Jackdaw breeds in of nest sites in nearby colonies, and colonies and feeds on insects and oth- the trend towards breeding sites near er . It forages near the prime food sources. nesting site in short-grass meadows and pastures with an abundant supply Buildings or trees: the trends of insects. Because human settlements differ are expanding and building density is Thanks to the «Avimonitoring» pro- rising, suitable foraging areas close gramme in the Canton of Zurich, the to the traditional nesting sites are be- population trend can be broken down 180 coming increasingly rare. With devas- by type of nest site since 2003. Overall, 160 tating consequences: Jackdaws need the population has increased some- 140 to cover larger and larger distances what, due mainly to birds nesting in to find food for nestlings, or resort to buildings, towers and radio masts. 120 kitchen scraps such as bread, pasta However, building nesters in particu- Index 100 and rice. The diminished amount or lar have seen a sharp decline in re- 80 quality of nestling food significant- cent years. Since 2015, a trend to- 60 ly reduces breeding success. There- wards smaller colonies has been ob- 40 fore, installing nest boxes for Jack- served. Tree-nesting Jackdaws have 1990 1995 2000 2005 2010 2015 daws is particularly effective in areas also recently seen some declines. Jackdaws can nest in buildings, but they of low-intensity agriculture, where the Despite the rising national trend for rely on areas with short vegetation for birds find sufficient natural and pro- the Jackdaw, the data from Zurich call foraging, e.g. pastures, meadows and tein-rich food for their young. for continued vigilance. fields.

140 Tree cavities 120 Buildings, radio masts 100

80

60 Number of pairs 40

20

0 2003 2005 2007 2009 2011 2013 2015 2017 2019 The national trend of the Eurasian Jack- Jackdaw population trend in the Canton of Zurich between 2003 and 2019, by type of daw has steadily increased between 1990 nest site. Source: Avimonitoring Canton of Zurich, BirdLife Zurich. and 2019. It is based on annual counts at about 160 sites.

11 BREEDING BIRDS

More accurate trends thanks to new calculation methods

Breeding bird indices are a pivotal in- 250 strument to assess a species’ situation, Opportunistic observations with date The chart shows how the dataset used to calculate and together they form the basis for Opportunistic observations without date the Swiss Bird Index SBI®. For common 200 trends for the Common Surveyed squares (MHB, BDM, atlas) Whitethroat developed species and wetland birds, the com- Monitoring wetlands over time. Apart from the mon breeding bird monitoring scheme considerable increase in 150 (MHB) and the wetland monitoring the number of records, it scheme (MF) allow us to form an ac- also highlights the large curate assessment of trends. Trends amount of undated re- 100 cords in the 1990s. in rare breeding birds (e.g. Red-- Thanks to the newly de- ed Pochard) and colonial species (e.g. veloped methods, these Common Tern) are also well docu- with records squares Kilometre 50 records and quantitative mented thanks to the good coverage data from territory map- of breeding sites in the wetland mon- ping surveys can be included in the trend itoring scheme (MF), observations re- 0 1990 1995 2000 2005 2010 2015 estimates. corded on ornitho, and, in some cases, species-specific monitoring projects. Species that are quite scarce and dif- ficult to detect, on the other hand, fall has increased over the years. Howev- are covered regularly and with about through the net. Among them, for ex- er, MHB and MF data are not includ- the same observer effort, which is cru- ample, grouse, woodpeckers and rare ed in this model. New methods devel- cial for the assessment of long-term songbirds. oped at the Swiss Ornithological In- trends. Furthermore, we can incorpo- stitute now allow us to use data from rate changes in density per kilometre Valuable combination of different different sources to calculate trends. square – a piece of information not data sources Besides opportunistic observations, available from opportunistic observa- Until recently, we calculated the pop- we can now also include quantita- tions. Finally, we can now include data ulation trends of these species using tive data from MHB, MF, «Biodiver- from recording cards that have no ex- a site occupancy model based on op- sity Monitoring Switzerland» (BDM) act date but were compiled for an portunistic observations (i.e. data from and the breeding bird atlases in trend entire month or season. These cards ornitho). The model accounts for the estimates. were commonly used to record ob- fact that a species may be present but This is valuable for two reasons: in servations in the 1990s. Failing to in- not detected, and that observer effort the monitoring projects, sample areas clude these data would result in an incomplete picture of the situation at that time. Common Whitethroat Rock Partridge

150 400 Differences in the 1990s especially 300 The trends calculated based on the 100 new method differ quite substantially 200 from the trends based only on oppor- Index Index 50 tunistic observations, especially for the Opportunistic observations only 100 1990s. An in-depth analysis has shown Combined that the new method provides more 0 0 accurate trends in many cases. 1990 1995 2000 2005 2010 2015 1990 1995 2000 2005 2010 2015 The breeding bird index calculated by combining the various data sources (red) compared to the index based solely on opportunistic observations (blue) for Common Whitethroat and Rock Partridge. The shaded area indicates the uncertainty of the estimate (standard error). In the case of the Common Whitethroat, the divergence in the 1990s is probably due to the fact that undated records were only included in the red curve. Weather-related fluctuations in the Rock Partridge population are greatly underestimated if quantitative data from territory mapping surveys are not included.

12 140

120

100

Index 80

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40 1990 1995 2000 2005 2010 2015 Including data from the wetland monitoring scheme as well as undated records gives us a more accurate picture of how steeply the European Turtle-dove population has declined. BREEDING BIRDS

Regular breeders in Switzerland Population trends for 174 regular breeding birds¹ analysed in Switzerland for the entire survey period (generally 1990–2019) and for the last ten years (2010–2019). Trends shown as +++ signify an increase by more than a factor of five, while ++ marks an increase between a factor of two and five and + an increase by less than a factor of two. The symbol • means that no sta- tistically significant change was detected. This is the case for populations that are actually stable but also for those that fluc- tuate heavily. Trends shown as – describe a decline by less than a factor of two, – – marks a decline between a factor of two and five and – – – a decline by more than a factor of five. Population sizes refer to 2013–2016:  = males, bp = breeding pairs.

Species Trend Trend Population Species Trend Trend Population 1990–2019 2010–2019 2013–2016 1990–2019 2010–2019 2013–2016

Common Quail • • 500–2000  Common Tern ++ • 580–760 bp Rock Partridge • ++ 2500–4500 bp Common Barn-owl – + 200–1000 bp Grey Partridge • – – – 5–10 bp Eurasian Pygmy-owl • • 800–2000 bp Hazel Grouse • • 3000–5500 bp Little Owl ++ + 115–150 bp Rock Ptarmigan – • 12 000–18 000 bp Boreal Owl – • 1000–3000 bp Western Capercaillie – + 380–480  Eurasian Scops-owl ++ • 30–40 bp Black Grouse • • 12 000–16 000  Northern Long-eared Owl3 + • 2000–3000 bp Common Eider • – – – 1–5 bp • • 6000–8000 bp Goosander ++ + 600–800 bp Eurasian Eagle-owl • • 200–230 bp Red-crested Pochard +++ • 210–300 bp European Honey-buzzard + • 500–1000 bp Common Pochard • • 6–9 bp Bearded Vulture +++ +++ 9–15 bp Tufted Duck + • 160–280 bp Golden Eagle + • 350–360 bp Gadwall ++ • 5–10 bp + • 3500–6000 bp Mallard + • 20 000–30 000 bp + • 1300–1700 bp Little Grebe • + 800–1300 bp Red Kite +++ + 2800–3500 bp Great Crested Grebe – • 3500–5000 bp Black Kite2 • 2000–3000 bp Black-necked Grebe • • 3–4 bp Eurasian Buzzard + • 15 000–20 000 bp Stock Dove + + 2000–4000 bp Common Hoopoe + • 180–260 bp Common Woodpigeon ++ + 130 000–150 000 bp European -eater +++ ++ 53–72 bp European Turtle-dove – – – 150–400 bp Common Kingfisher + • 400–500 bp Eurasian Collared-dove + • 15 000–25 000 bp Eurasian Wryneck • + 1000–2500 bp European Nightjar – – 40–50 bp Grey-faced Woodpecker3 – – – 300–700 bp Alpine Swift ++ • 1800–2300 bp Eurasian Green Woodpecker + • 10 000–17 000 bp Pallid Swift ++ • 29–36 bp Black Woodpecker ++ + 6000–9000 bp Common Swift2 • 40 000–60 000 bp Three-toed Woodpecker • + 1000–2500 bp • • 15 000–25 000  Middle Spotted Woodpecker ++ + 1700–2100 bp Western Water Rail • + 500–800 bp Lesser Spotted Woodpecker + • 1500–3000 bp Corncrake ++ • 15–40  ++ • 70 000–90 000 bp Spotted Crake • • 10–20 bp Common Kestrel ++ + 5000–7500 bp Common Moorhen + + 1000–2000 bp Eurasian Hobby + • 500–1000 bp Common Coot + • 5000–8000 bp Peregrine Falcon ++ • 260–320 bp White Stork ++ ++ 370–460 bp Eurasian Golden Oriole + • 3000–4500 bp Common Little Bittern • • 90–120 bp Red-backed Shrike – • 10 000–15 000 bp Grey Heron + + 1600–1800 bp Woodchat Shrike – – – • 0 bp Purple Heron +++ +++ 6–17 bp Red-billed Chough ++ • 70–80 bp Great Cormorant +++ ++ 1200–2100 bp Yellow-billed Chough2 • 11 000–21 000 bp Little Ringed Plover • • 90–120 bp + • 60 000–75 000 bp Northern Lapwing – + 140–180 bp Eurasian Magpie ++ • 35 000–40 000 bp Eurasian Curlew – – – • 0 bp Northern Nutcracker • • 20 000–25 000 bp Eurasian Woodcock – • 1000–4000  Eurasian Jackdaw + • 1250–1500 bp Common Snipe – – – • 0–1 bp Rook +++ ++ 5800–7300 bp Common Sandpiper • + 70–90 bp Common Raven + • 2000–3000 bp Black-headed Gull – – • 560–800 bp Carrion Crow ++ • 80 000–120 000 bp Mediterranean Gull • • 0–5 bp Coal Tit2 • 400 000–600 000 bp Mew Gull • • 0–3 bp Crested + – 90 000–110 000 bp Yellow-legged Gull +++ • 1240–1430 bp Marsh Tit + – 70 000–100 000 bp

14 BREEDING BIRDS

Species Trend Trend Population Species Trend Trend Population 1990–2019 2010–2019 2013–2016 1990–2019 2010–2019 2013–2016

Alpine or Willow Tit2 • 70 000–95 000 bp Bluethroat ++ • 5–12 bp Eurasian Blue Tit ++ • 200 000–300 000 bp Common Nightingale + • 1700–2200 bp Great Tit + • 400 000–550 000 bp European Pied Flycatcher2 • 17 000–22 000 bp Woodlark • + 250–300 bp Black Redstart + • 300 000–400 000 bp Eurasian Skylark – • 25 000–30 000 bp Common Redstart • • 12 000–18 000 bp Bearded Reedling + ++ 80–110 bp Rufous-tailed Rock- – + 2000–3000 bp Melodious Warbler + • 300–350 bp Blue Rock-thrush • • 15–25 bp Icterine Warbler – – • 100–150 bp Whinchat – – • 5000–7000 bp Marsh Warbler • • 3000–6000 bp Common Stonechat + + 1500–2000 bp Common Reed-warbler • • 9000–11 000 bp Northern Wheatear + • 40 000–60 000 bp Great Reed-warbler + ++ 270–320 bp + • 200 000–400 000 bp Savi’s Warbler + • 280–310 bp Common Firecrest • ++ 250 000–400 000 bp Com. Grasshopper-warbler + • 150–250 bp Alpine Accentor – • 25 000–40 000 bp Northern House Martin – • 70 000–90 000 bp Dunnock + • 200 000–250 000 bp Barn Swallow • + 70 000–90 000 bp + • 450 000–550 000 bp Eurasian Crag Martin + + 7000–9000 bp Eurasian Tree Sparrow + • 80 000–95 000 bp Collared Sand Martin – + 2300–3000 bp White-winged Snowfinch – • 6000–9000 bp Western Bonelli’s Warbler ++ • 40 000–60 000 bp Tree Pipit – • 50 000–70 000 bp Wood Warbler – – • 5000–7500 bp Meadow Pipit – – • 500–800 bp Willow Warbler – – – 4000–5000 bp Water Pipit • + 150 000–200 000 bp + • 250 000–300 000 bp Western Yellow Wagtail + • 300–340 bp Long-tailed Tit + • 20 000–35 000 bp Grey Wagtail • • 17 000–20 000 bp + • 700 000–800 000 bp White Wagtail – • 90 000–110 000 bp Garden Warbler – – 35 000–50 000 bp Common Chaffinch + • 900 000–1 100 000 bp Barred Warbler – – – • 0–5 bp Hawfinch • • 13 000–17 000 bp Lesser Whitethroat • • 17 000–23 000 bp Common Rosefinch • • 50–70 bp Common Whitethroat + • 1800–2500 bp Eurasian Bullfinch – • 40 000–75 000 bp Short-toed Treecreeper + • 45 000–55 000 bp – – 90 000–120 000 bp ++ • 75 000–100 000 bp Common Linnet • + 25 000–30 000 bp – – 110 000–170 000 bp Redpoll • • 15 000–20 000 bp Wallcreeper – • 1000–2500 bp Red Crossbill ++ • 25 000–35 000 bp Northern + • 400 000–550 000 bp European Goldfinch – + 50 000–70 000 bp White-throated Dipper + • 6000–8000 bp Citril – • 10 000–20 000 bp Common Starling • + 120 000–140 000 bp European Serin • • 35 000–45 000 bp + • 130 000–150 000 bp Eurasian Siskin2 • 10 000–16 000 bp Song Thrush + + 300 000–350 000 bp Corn Bunting – – – 80–110 bp Eurasian Blackbird + • 500 000–700 000 bp Rock Bunting + • 7000–10 000 bp Fieldfare – • 40 000–45 000 bp Ortolan Bunting – – – – – – 1–5 bp Ring Ouzel – • 50 000–75 000 bp Cirl Bunting + + 1000–1500 bp Spotted Flycatcher – • 35 000–55 000 bp Yellowhammer • – 65 000–75 000 bp European Robin + • 450 000–650 000 bp Reed Bunting – • 1700–3000 bp

1 This includes species categorised as regular breeders at least once since 1990 (i.e. the species has bred in Switzerland in at least nine of ten consecutive years). 177 species belong in this category, not counting Further information (i.e. Mute Swan, Ruddy , Common Pheasant). No assessment is possible for www.vogelwarte.ch/state/breeding White-backed Woodpecker, Collared Flycatcher and Italian Sparrow due to lack of data. 2 Survey period 1999–2019 3 Survey period 1996–2019

Irregular and exceptional breeders Reference Since 2000, a further 28 species have bred in Switzerland irregularly or excep- Müller, C. (2020): Seltene und bemerkens- tionally. Their breeding occurrences are documented as consistently as possi- werte Brutvögel 2019 in der Schweiz. Orni- ble (table available online in the section «Further analyses»). thol. Beob. 117 (in press).

15 In late April the Collared Flycatcher appeared in surprisingly large numbers, especially in Ticino and the Rhone Valley.

Spring and autumn invasions

The Glossy Ibis population is growing Spectacular appearance of the have never been seen in such large in southern Europe, especially in Spain Collared Flycatcher numbers before. Sightings were less and in the Camargue. Since 2010, it One of the most impressive events numerous in the rest of Switzerland has appeared in Switzerland annual- of 2019 was the big wave of return- and occurred mainly on the last three ly in steadily rising numbers. In spring ing Collared Flycatchers, especially in days of April. A constant, strong south- 2019, influxes occurred between 19 Ticino and the Rhone Valley. From 23 easterly wind over the central Mediter- April and 17 May with observations in to 30 April, the species was observed ranean favoured the influx, which was 12 places; the largest group, consist- at about 50 sites between Locarno TI registered in other countries as well, ing of 11 birds, was seen in the Fanel and Giubiasco TI alone. The invasion leading to an invasion of unprecedent- nature reserve BE. It was the greatest peaked on 25 April, with 15 birds in the ed magnitude in Catalonia. The spe- influx of this species recorded in Swit- Maggia Delta TI and at least 28 in the cies is extremely scarce in Spain, and zerland to date. Magadino Plain TI. Collared Flycatchers only 79 records had existed until the

30 March April May June July

25 2019 ø 2009–2018 20

15

10 % of complete lists

5

0 11 14 17 20 23 26 29 32 35 38 41 Five-day periods The Wood Warbler normally stops over in small numbers in Switzerland. But in late April 2019 it was the most abundant warbler in some areas. The reasons lie in a constant, strong southeasterly wind and a weather-related blockage that prevented the birds from continuing their migration.

16 MIGRANTS

it was a Europe-wide phenomenon. In 2018 2019 certain years, large migration move- ments of birds from northern and east- ern Europe are observed in this nor- mally sedentary species. Influxes of Eurasian Jays were previously record- ed in Switzerland in 1977, 1983, 1996, 2004 and 2010. Systematic surveys by the Ornithologische Arbeitsgemein- schaft Bodensee (OAB) on the north- Unlike the previous year, there were many sightings of Collared Flycatchers in late ern shore of Lake Constance record- April 2019 on the Mediterranean coasts of Catalonia and southern France. ed more than 130 000 Jays between 15 September and 20 October 2019, more than double the previous re- end of 2017, most of them from the Woodpigeon even crossed the thresh- cord from 1977. On 11 October, over . Between 19 and 30 old of 100 000 birds per day. The old 42 000 birds were counted on a single April, 120 Collared Flycatchers were re- 2018 record of 74 319 birds was sur- day. The invasion was also noted on ported in Catalonia alone. There were passed on 13 October 2019, when the Alpine passes: on Col de Bretolet many sightings on the south coast of 103 700 Woodpigeons were record- VS, for instance, 135 Jays were ringed France as well. ed near Liestal BL. On the same day, in 2019, compared to an average of The notable spike in migrating 113 121 individuals passed through only 11 birds between 1954 and 2018. Wood Warblers in late April suggests Wolschwiller in neighbouring France; Two thirds of the ringed birds were ju- that these birds benefited from the as many as 177 753 birds had been veniles. Such mass migrations are in same airstream. The number of Wood counted there on 11 October. Num- fact often triggered by high breeding Warblers reached a peak of 60 birds bers north of the Swiss border were success combined with a local food in the Maggia Delta TI on 25 April, of a similar magnitude: according to shortage. and 50 individuals were recorded near reports on ornitho.de, the passage of Cressier NE on 28 April. In Catalonia, Woodpigeons in Germany was much this migrant, relatively uncommon in stronger than in the two previous Spain, was also seen in much larger years. Falsterbo at the southern tip of numbers than in previous years. Sweden reported a record high of al- most one million migrating Woodpi- Woodpigeons in their thousands geons in autumn 2019. In autumn 2019, the passage of most diurnal migrants was phenomenal. In Massive invasion of Eurasian Jays October, especially in a fine-weath- The extraordinary passage of Eurasian er period mid-month, daily totals Jays in autumn 2019 will also be re- Further information reached record highs for several spe- membered. The interactive maps on www.vogelwarte.ch/state/migration cies. For the first time, the Common EuroBirdPortal (EBP) clearly show that

80 Aug. Sept. Oct. Nov. Dec.

70

60

50

40

30

% of complete lists 20 2019 ø 2009–2018 10

0 43 46 49 52 55 58 61 64 67 70 73 Five-day periods In autumn 2019, loose groups of Eurasian Jays were seen on passage through Switzerland in unusually large numbers. The invasion peaked between mid-September and mid-October.

17 MIGRANTS

Flocks of migrating cranes fly over Switzerland at all times of the day and night, giving their loud, trumpeting calls.

Cranes in the sky over Switzerland

Towards the end of the 20th century, mid-November. Spring migration migration corridor starts in Scandi- the Common Crane was a scarce pas- from early March to mid-April was navia, western Poland and Germa- sage migrant in Switzerland. There insignificant. Crane sightings were ny, stretches across France from the was an average of 17 records per so rare because Switzerland lies out- northeast to the southwest, and ends year, most of them from autumn mi- side of the traditionally quite narrow in Spain. A second pathway leads gration between mid-October and main migration routes. The western from across the Baltic States,

1600

1400

1200

1000

800

600 Presence index Presence 400

200

0 1990 1995 2000 2005 2010 2015 Data from various European online portals show the new migration Autumn migration of Common Cranes (1 September – 31 December) routes connecting Hungary with France both north and south of has significantly increased in Switzerland since 2011. This was the the Alps. first year in which the connection between the Hungarian and the western migration routes was used by a large number of birds.

18 MIGRANTS

Poland and Hungary to North Afri- ca. There are additional routes fur- ther east.

A shortcut to the west Since 2011, autumn sightings have drastically increased in Switzerland. The same phenomenon was observed in Austria, southern Germany and northern Italy. According to a study that analysed the migration move- ments in autumn 2013 in detail using data from internet platforms such as ornitho.ch or ornitho.de, these birds set out from Hungary heading west. Some of them reached the western migratory pathway via the north- ern Pre-Alps, others took a southern The largest flocks occur in autumn in northern Switzerland. The dots indicate the maximum route around the Alps towards south- number of individuals per site between September and December during 2011–2019: ern France, where the number of win- white = 1–50 ind., yellow = 51–150 ind., = 151–300 ind., red = 301–800 ind. tering Cranes has seen a marked in- crease since 2010. Numbers of winter visitors in the Camargue document this trend: more than 14 000 individ- uals were counted in 2017, up from a mere 200 in 2004. Ring recoveries Winterthur ZH and Anières GE on the drivers of this positive trend. In in this area tell us that 89 % of the 13 November 2019. It took the birds addition, climate change appears ringed winter visitors came from Fin- 6 hours and 45 minutes to cover this to have benefited survival during land. One of these birds had previ- stretch of 230 km, which corresponds migration and on the wintering ously been recorded in Hungary, thus to an average speed of 34 km/h. While grounds, at least so far. confirming the connection between only about 30 Cranes passed through the Hungarian and the westernmost the defile in the Jura near Fort l’Écluse migration corridors. F southwest of Geneva in the 2000s, this figure has skyrocketed in recent Passage over Switzerland years, reaching 1652 birds in 2018. The massive migration observed in In with the trend during autumn Switzerland and southern Germa- migration, the number of winter ny in autumn 2011 was probably visitors and spring migrants has also encouraged by the strong easter- increased in Switzerland, though to a ly wind dominating at the time. But lesser extent. there seem to be other factors that make this shortcut towards the west Positive trend worthwhile, as it continued to be fre- The current trends match the over- quently used in the following years all increase in Crane population siz- and has since become an established es and range expansion in Europe, new pathway. which has led to new breeding re- The map of all autumn sightings cords in France and the Netherlands. in Switzerland since 2011 shows that As is to be expected, the number of most of the data come from the Central migrants on the western route has Plateau and northern Switzerland. risen from 35 000 individuals in the The birds probably then traversed 1980s to more than 80 000 in 1995 the Jura in a westerly direction, as and up to 350 000 in autumn 2015. only few larger groups were reported At least another 150 000 birds use in the Lake Geneva region. Some the corridor between the Baltic States kept to a southwesterly direction, and Hungary. The restoration of wet- however, like the group of 66 birds lands that serve as breeding or stopo- that was repeatedly reported between ver sites for Cranes is probably one of

19 METHODOLOGY

Recording: how and why?

Never before have records of birds in

Switzerland been used as frequent- 2020 ly and as widely as today, e.g. for da- IS revision IS revision tabase requests from ecological con- IS revision 2004 IS revision sultants, authorities and conservation 1994, IS revision Launch NaturaList groups. We are extremely grateful to Launch ornitho.ch our volunteer collaborators for contin- introduction of H species introduction ries and recording options ries and recording

uing their excellent recording work, es- collection begins (IS) Record Introduction of complete lists Introduction

pecially the recording of breeding birds. of species catego - Introduction We understand that many people like to have clear guidelines, e.g. regard- ing which species to record when. On our side, we appreciate knowing exact- ly which data were collected according to the guidelines and which were not. 1960...1980 1984 1987 1994 1999 2004 2007 2014 2017 2020 Only with this information can we fil- Record collection with clear guidelines on recording options and species categories was ter out the data that will yield the most introduced in 1984 and has proven very effective. Several revisions have since taken place. accurate results given a certain research question.

Guidelines updated as of particularly important for category A was surveyed and for how long. Sec- 1 January 2020 species. The principle «all or nothing» ondly, the lists not only provide infor- The abundances of certain species have applies here; someone recording ob- mation on the birds that were actually changed markedly over the past years, servations using the «standard» option recorded, but also on those not found. for example those of Red-crested Po- is requested to record all sightings of We thus gain additional information chard, Red Kite and Yellow-legged Gull. A species and also all observations of that helps us in phenological analyses The last revision dates back to 2004, so B species if they merit an atlas code of and models. Other databases such as an update was overdue. The changes 7 or higher. The number of birds de- BirdTrack and eBird also encourage the that took effect in 2020 focused pri- tected should be added for A species use of complete lists. Switzerland is in marily on updating the assignment whenever possible. As an alternative a good position, with currently more of species categories and making the to the«standard» option, there is also than 30 % of records reported using guidelines more specific. a «mini» recording option. If observers complete lists. choose this option, they don’t have to Consistent recording is crucial follow the guidelines, but accept that Opportunistic observations still make records collected this way will only be up a large portion of the records we used in certain analyses. receive. In order to put these to the best possible use, we need to be sure The value of complete lists they were collected according to the We have good reasons for promoting «standard» recording option, i.e. ac- the use of complete species lists. First cording to clear guidelines. This is of all, such a list tells us when an area

Category Symbol on Significance Examples When to record? ornitho.ch Recording bird sightings A 1 Northern Scarce and rare Northern Lapwing, All sightings year- A list of all species found in Switzerland Lapwing species, vagrants, Red-necked Grebe, Little round escapees Bunting, Mandarin Duck and their species categories is available here: www.vogelwarte.ch/id (available in German, French or Italian). More on re- B 1 Tufted Waterbirds and colo- Tufted Duck, Collared All sightings with cording: www.ornitho.ch/instructions Duck nial species that breed Sand Martin atlas code 7 or higher in Switzerland rarely (strong indication of or in small numbers breeding) C 1 Common Common species Common Chaffinch, At observer’s discre- Chaffinch Western Yellow Wagtail tion

20 The Red-crested Pochard is now classi- fied as a category B species. Most help- ful to us are records that give a strong indication of breeding, i.e. atlas code 7 and higher. In the afternoon, Red Kites gather in free-standing trees or high hedges.

Wintering Red Kites on the increase

Few other bird species have seen such 2007/08. The project has since grown 4300 individuals – as usual a signifi- dynamic growth in the past decades as into a veritable «enterprise» involv- cantly smaller number than in Novem- the Red Kite. Widespread and common ing about 170 volunteers. In Novem- ber, but again a record high for the in the Middle Ages, then all but oblite- ber 2019, 63 roosts were occupied January counts. About 90 % of winter rated by guns and poison, the species by 5200 Red Kites, and as many as visitors are adult birds. Residents are has recolonised large parts of Switzer- 67 roosts in January 2020, totalling joined by migrants from Germany. The land as a breeding bird since 1950. In recent years, it has continued its ex- 160 pansion into Grisons and Valais. The 5000 species excels at adapting to new cir- 140 cumstances and taking advantage of 120 available niches and opportunities. Its 4000 adaptability is reflected in a growing number of wintering birds as well. 100 3000 80 Roost counts document increase A veritable surge has taken place since 2000 60 the turn of the century. The first Red Days with snow-cover Wintering population Kites started wintering in the Canton 40 of Zurich and the Ajoie JU in the winter 1000 of 1969/70. In the winter of 2002/03, 20 11 roosts with at least 1000 birds were 0 0 known. Prompted by similar surveys in 1969 1975 1981 1987 1993 1999 2005 2011 2017 France, Red Kite expert Adrian Aeb- Wintering population trend of the Red Kite at roosts since 1969 (red, left axis). The de- ischer began conducting more sys- crease in days with snow-cover (blue columns, right axis) makes foraging easier for the tematic roost counts in the winter of Red Kite (weather station Lucerne; source: MeteoSwiss).

22 WINTER VISITORS

The birds fly to the roost at dusk. The site can change from day to day. In Switzerland most resident Red Kites are adult birds. colour and moulted tail indicate that this individual is an adult.

increase is due to the growing breed- and feeding stations as well as from the ing populations and to behavioural supply of small mammals and earth- changes. worms. Winters with little snow make hunting easier. It comes as no surprise Growing percentage of that Red Kites are increasingly seen at resident birds altitudes of 1000 m and above even in The older Red Kites get, the less like- winter! ly they are to migrate to the tradition- al wintering grounds located primari- ly in Spain, but also in southern France and Portugal. Studies by the Swiss Or- nithological Institute have shown that Further information food is abundant in Switzerland all year www.vogelwarte.ch/state/winter round. Red Kites profit from roadkill

2002 2019

In winter 2002/03, 11 roosts were known and the population was estimated at about 1000 Red Kites. In November 2019, 5300 birds occupied 63 roosts. White = winter records; yellow = roosts with up to 20 individuals; orange = roosts with 21–99 ind.; red = roosts with more than 100 ind. Source: Adrian Aebischer.

23 WINTER VISITORS

Mild autumn, few winter visitors

November 2019 was mild and rainy; it from the central European breeding rained on the Sunday of the waterbird population, but ring recoveries also counts as well, so November counts point to migrants from eastern Eu- were conducted a day earlier in many rope. In the past five years, the winter- places. Following a warm month of ing population of Mallards in Switzer- December, January was dominated by land has declined sharply. This trend high-pressure periods, providing ide- may be due to the absence of win- al conditions for the January counts. ter visitors from eastern Europe, given that the breeding population in Swit- Mallard population at a low zerland and in Europe is currently fair- Overall, around 400 000 waterbirds ly stable. Various dabbling ducks and were counted in Switzerland (includ- the Tufted Duck (68 000) had low No- The breeding population of Mallards is ing cross-border areas) in November vember counts as well. stable or slightly increasing in Switzer- 2019. This is by far the lowest fig- Observers were surprised by re- land, but the wintering population has decreased markedly in the past five years. ure since November counts began in cord-high numbers both in Novem- 1991, which may be partly due to the ber and in January of Eurasian Curlew bad weather, but is mainly a result of (1700 individuals in November, 1900 climate-related changes in the migra- in January) and Common Moorhen tory behaviour of many species. Spe- (1100 in November, 1000 in January). cies with all-time lows in November The Egyptian Goose counts were also included Common Pochard (62 000 at an unprecedented high (160 indi- Declines on Lake Geneva, individuals) and Mallard (32 000). The viduals in November, 260 in January). increases on Lake Neuchâtel January count was at a record low for In addition, new highs were reached Trends over the past 20 years vary de- Mallards as well (38 000). Since the by Common Snipe (400 ind. in No- pending on the site. On Lake Geneva, 1990s, the wintering population of vember), Ferruginous Duck (110 ind. numbers are declining steeply espe- Mallards has ranged between 40 000 in November), Great White Egret cially on the Swiss side and have now and 50 000 individuals in November (540 ind. in January), Eurasian Wig- reached the lowest level since the cen- and between 50 000 and 60 000 in eon (4500 ind. in January) and Black- sus began in 1967. The surface tem- January. Most of these birds stem necked Grebe (8000 ind. in January). perature of Lake Geneva is warmer than that of other lakes north of the Alps well into the winter. Many water- birds relocate to Lake Geneva when the shores of other lakes on the Cen- 700 000 tral Plateau freeze, but that happens November less and less. The populations on Lake January 600 000 Neuchâtel show a long-term posi- tive trend. Its extensive shallow-wa- 500 000 ter zones offer excellent feeding con- ditions for wintering waterbirds – as 400 000 long as they do not freeze over. As a further advantage, birds are sheltered 300 000 from disturbance in the protected na- ture reserves of the Grande Cariçaie.

Number of individuals 200 000 This is not always the case on other waterbodies.

100 000 Human disturbance has reached a level where the current protective measures in sanctuaries for water- 0 1991/92 1997/98 2003/04 2009/10 20015/16 birds and migratory birds are not al- ways sufficient. Hunting waterbirds, a Trend of November and January waterbird counts (total of all species) on Swiss waterbodies including the German and French parts of Lake Constance and Lake Geneva. The chart cov- major disturbance in the past, is now ers the entire period since the first November count in 1991. Numbers were at an all-time prohibited in the reserves, but oth- low in November 2019. er sources of disturbance (stand-up

24 WINTER VISITORS

November + 10 000 ind. + 5000 + 1000 ~ – 1000 – 5000 – 10 000

The record-high number of wintering Eur- asian Wigeons in January 2020 is in line with the long-term increase of this species as a winter visitor. The Rhine Delta on Lake Constance, where the Eurasian Wigeon is commonly found on grassy areas near the water, is an extremely important wintering site for this species.

paddling especially, but also manu- January ally propelled boats and motorboats) are often permitted and have become more popular in recent years even in winter – partly because of the mild temperatures. More attention must be brought to the problem of disturb- ance, or we will miss the conserva- tion goal for waterbird and migrato- ry bird reserves – preserving the area as a stopover and feeding site for win- tering waterbirds – by an ever larg- er margin. The growing population of Great Cormorants has led to increasing pres- sure to drive them away even from nature reserves. But such measures tend to affect other species much Changes in waterbird numbers per count stretch in November (top, 1999–2018) and Janu- more than the actual target. Great ary (bottom, 2000–2019). The size of the symbols corresponds to the estimated change, Cormorants are less shy than most calculated using a linear model. Stretches showing no clear change were marked with a black dot. The transparent marks designate counts of stretches outside of Switzerland; on winter visitors, which continue to the Obersee part of Lake Constance, the counts are grouped by country. use Swiss lakes and rivers in numbers of international importance. By the time the Great Cormorant has been chased away, many dabbling and div- ing ducks have long left. Their flight Further information causes them to waste valuable en- www.vogelwarte.ch/state/winter ergy, which has been shown to re- duce breeding success in the follow- ing spring.

25 WINTER VISITORS

The traditional roost site in the Rhine port in Basel («Dreiländereck») is occupied by several thousand Black-headed Gulls every winter.

Ups and downs in Black-headed Gull numbers

Towards the end of the 19th centu- extended into the second half of the fear of humans and was able to exploit ry, Black-headed Gull numbers were 20th century. Black-headed Gulls ben- these new resources. At the same time, low in Europe as a result of direct per- efited from rubbish dumps, feeding losses through egg collection and di- secution, egg collection and the de- in cities, the spread of cultivated land, rect persecution dwindled. Currently, struction of breeding habitat. The re- and an increasingly open agricultur- the European breeding population is covery that followed brought a sub- al landscape. Thanks to new conser- estimated at 1.3–2 million pairs. The stantial increase in population size that vation legislation, the species lost its Black-headed Gull is one of the most common bird species on Swiss lakes and rivers in winter. Locally, it roosts in remarkably large numbers. The larg- 1000 ind. est roost ever recorded in Switzerland 500 ind. < 100 ind. was at the lower end of Lake Zurich. 100 bp When wintering numbers were at their < 50 bp highest, in February 1979, an estimat- ed 25 000 Black-headed Gulls regular- ly went there to roost. For the entire Central Plateau, the population was estimated at up to 180 000 individuals.

Decline in the past 40 years Since then, the wintering population of Black-headed Gulls in Switzerland has dropped sharply. It is impossible to determine the exact extent of the de- , as no national roost count has been conducted since 1979, and the The Black-headed Gull is a widespread winter visitor in Switzerland (blue), as documented species has only been included in the by the average January counts in 2015–2019. It is a much scarcer breeding bird (red; the waterbird census consistently in the map shows colonies recorded in 2013–2016). last few years. Furthermore, flocks

26 WINTER VISITORS

100 000

80 000

60 000

40 000 Number of individuals

20 000

0 1971 1977 1983 1989 1995 2001 2007 2013 2019 January totals of the past 50 years based on the results of the water- The waterbird census currently records about 40 000 Black-headed bird census. Missing values were calculated for each stretch by inter- Gulls. Despite the decline, this species is still one of the most common polation. The decline in the wintering population of Black-headed winter visitors in Switzerland. Gulls was particularly marked in the 1980s and 1990s. The actual numbers are presumably quite a bit higher, because only birds on and near waterbodies were counted.

that gather away from waterbodies earthworms shrinks when larger are- on feeding have reduced the availa- are generally not counted. as are tilled in one go thanks to fast- bility of food. The Black-headed Gulls winter- er and more efficient machinery. Pre- ing in Switzerland come from various dation on eggs and nestlings by larg- Future trend is uncertain European countries. The drop in the er gull species also reduces breeding It is not clear whether the species will Swiss wintering population reflects success. On North Sea coasts, pop- persist as a breeding bird in Switzer- the international situation. In west- ulations of European Herring Gulls land in the long term. The survival of ern and central Europe, the breeding were artificially kept small up until most colonies will depend on specific population has more or less halved the 1970s to protect the broods of conservation measures. Besides large since 1990. Among the reasons cited smaller species. Since then, the popu- gulls, terrestrial predators or the Eur- for the decline are changes in farming lations of several large gulls have sub- asian Eagle-owl can impact breeding practices that impact the food sup- stantially increased, locally causing success as well. The predicted range ply during the nestling period. Earth- Black-headed Gull colonies to disap- shift due to climate change may lead worms are an important source of pear and probably impacting the pop- to the Black-headed Gull disappearing nestling food. Intensified farming can ulation trend at a larger scale as well. from parts of central Europe. Accord- reduce the supply of worms. In addi- Outside of the breeding season, the ing to the European Red List, the spe- tion, the window for hunting exposed closure of rubbish dumps and bans cies is not considered threatened. Lo- cally, however, further declines are to be expected. Other species like Com- mon Pochard, Tufted Duck and Black- necked Grebe could also be affected, as they like to nest in Black-headed Gull colonies for protection against predators.

Farming activities cause a short-term boost in the food supply.

27 WINTER VISITORS

Wintering waterbirds in Switzerland Population trends for waterbirds in Switzerland for the entire survey period (1967–2020) and for the last 20 years (2001– 2020). Trends shown as +++ signify an increase by more than a factor of five, while ++ marks an increase between a factor of two and five and + an increase by less than a factor of two. The symbol • means that no statistically significant change was detected, which also applies to populations that fluctuate heavily. Trends shown as – describe a decline by less than a factor of two, – – marks a decline between a factor of two and five and– – – a decline by more than a factor of five. The Jan- uary count 2020 also includes the German and French parts of Lake Constance and Lake Geneva.

Species Trend Trend Individuals Species Trend Trend Individuals 1967–2020 2001–2020 January 2020 1967–2020 2001–2020 January 2020

Mute Swan + + 7387 Common Teal + + 7458 Whooper Swan +++ ++ 835 Little Grebe – • 3461 Tundra Swan ++ 10 Red-necked Grebe • – – – 24 Barnacle Goose • 7 Great Crested Grebe + + 36 554 Canada Goose • 5 Horned Grebe ++ ++ 22 Greylag Goose +++ +++ 1538 Black-necked Grebe ++ ++ 8037 Bean Goose – – – – – – 2 Common Moorhen + 1018 Gr. White-fronted Goose +++ – 4 Common Coot – – 87 526 Long-tailed Duck ++ • 2 Red-throated Loon +++ • 15 Common Eider – – – 35 Arctic Loon +++ + 113 Velvet Scoter ++ + 33 Common Loon • • 4 Common Scoter • • 2 Eurasian Bittern – 13 Common Goldeneye – – – 4120 Grey Heron ++ + 1907 Smew – – – – 20 Great White Egret +++ 537 Goosander ++ + 5828 Great Cormorant +++ • 5886 Red-breasted Merganser ++ • 97 Eurasian Curlew + 1940 Egyptian Goose +++ 265 Common Snipe ++ 189 Common Shelduck +++ + 58 Common Sandpiper + 77 Ruddy Shelduck +++ 698 Little Gull +++ +++ 0 Mandarin Duck + 59 Black-headed Gull – – 45 102 Red-crested Pochard +++ ++ 31 202 Mediterranean Gull • +++ 5 Common Pochard ++ – 66 117 Mew Gull – – – 1890 Ferruginous Duck +++ ++ 75 Lesser Black-backed Gull • – 18 Tufted Duck ++ – 103 725 European Herring Gull – 17 Greater Scaup • – – 17 Yellow-legged Gull ++ 4476 Garganey • • 0 Caspian Gull 160 Northern Shoveler +++ • 754 Yellow-l./Herring/Casp. G. 731 Gadwall +++ + 11 506 Great Black-backed Gull • • 1 Eurasian Wigeon +++ ++ 4459 Common Kingfisher + 377 Mallard – – 37 552 White-throated Dipper + 823 Northern Pintail +++ ++ 1296 Grey Wagtail + 728

+++ increase > factor of 5 ++ increase between factor of 2 and factor of 5 + increase < factor of 2 • not significant or fluctuating – decline < factor of 2 – – decline between factor of 2 and factor of 5 – – – decline > factor of 5

Trend 1967–2020 Trend 2001–2020 (43 species) (60 species) Further information For most species, the long-term trend is positive. Egyptian Goose, Ruddy Shelduck and www.vogelwarte.ch/state/winter Great White Egret have shown the strongest increase in the last 20 years.

28 The numbers of wintering Great White Egrets have multiplied in the past 20 years. In January 2020, 537 individu- als were counted in all of Switzerland, a new record for the waterbird census. The Cantabrian Mountains in northwestern Spain: the terrain and the traditional types of land use sustain a rich biodiversity at a small spatial scale.

Growing international responsibility for Switzerland

Mountains are home to about a quar- lifeforms is mainly due to geographical small-scale land use. But for several ter of terrestrial biodiversity worldwide features and human impact: steep gra- decades now, traditional forms of land and almost half of the world’s biodi- dients and varying exposures create management have been in decline. To- versity «hotspots». In Europe, too, the an abundance of different living con- gether with global warming, which af- mountain ecosystems are extreme- ditions in a relatively small area. This fects mountains more strongly than ly diverse and cover about 36 % of natural diversity has been increased elsewhere, this trend has caused liv- the continent. The great diversity of over the centuries by the effects of ing conditions to change drastically for many species – the unique diver- sity of mountain habitats is increas- ingly at risk.

Europe-wide study reveals clear differences An international study with the par- ticipation of the Swiss Ornithological Institute has examined, for the first time, how changes in habitat and cli- mate across Europe relate to chang- es in bird populations. The study an- alysed the population trends of 44 al- bird species, i.e. species that occur above the tree line. The data The Northern Wheatear is the only species to occur in all four mountain regions included from 12 countries were analysed for in the study. While the population in the is declining, it is increasing in Europe as a whole as well as for four the Alps and stable in the Fennoscandian and British mountains. large European mountain regions:

30 INTERNATIONAL NEWS

Fennoscandia, UK upland, southwest- ern mountains (Pyrenees, Iberian Pen- insula) and southern mountains (Alps, Apennines). Overall, mountain bird species declined by 7 % during 2002– 2014, while mountain specialists even showed a significant decline of 10 %. The Fennoscandian and Iberian mountain birds declined more mark- edly, on average, than those in the UK and in the Alps. Climate change is con- sidered one of the main drivers of this negative trend in mountain bird popu- lations. The trend may have been less marked in the Alps because birds can still move to higher altitudes in this In Fennoscandia, the Common Redshank is a mountain bird. massive range, thus mitigating the negative effects of climate change. The Swiss breeding bird atlas 2013–2016 traditional refuges and thus the surviv- has already shown that alpine species al of species like Whinchat and Corn- in Switzerland saw a greater altitudinal crake. Farmland in steep or remote ar- range shift than species occupying low- eas is abandoned and becomes over- er altitudes. This means that our coun- grown with bushes and eventually try’s international responsibility in the forest, causing habitat to disappear conservation of mountain bird species for species of open landscapes. The will continue to grow. Swiss Ornithological Institute is engag- ing with partners to find solutions that Agriculture has a responsibility will enable the long-term survival of for bird conservation mountain birds in Switzerland despite Besides the challenge of climate rising temperatures. The vast moun- change, biodiversity in the moun- tain ranges of the Alps play a key role tains is coming under increasing pres- in species conservation not only in sure from changing land-manage- Switzerland, but in Europe. Further information ment practices. Intensified land use www.vogelwarte.ch/state/international in productive locations threatens the

140 140

120 120

100 100 Index Index

80 80 Fennoscandia UK upland Specialists Generalists Alps and Apennines Pyrenees and Iberia 60 60 2002 2004 2006 2008 2010 2012 2014 2002 2004 2006 2008 2010 2012 2014

For the period 2002–2014, the mountain bird indicator for Europe Mountain birds in the Alps and Apennines and in the UK upland areas shows that mountain specialists are in decline, while the trend for showed more stable trends on average than those in Fennoscandia generalists has remained largely stable. and in the Pyrenees and Iberia.

31 INTERNATIONAL NEWS

EBBA2 – a unique compilation of data on the breeding birds of Europe

One of the most ambitious faunistic How many bird species breed research projects ever undertaken is in Europe? nearing completion: the second Euro- During the period 2013–2017, 596 European Breeding Bird Atlas 2: distribution, abundance and change pean Breeding Bird Atlas (EBBA2) will breeding bird species were recorded. The new atlas will be published by Lynx be published towards the end of 2020. Europe is in fact a peninsula of the Edicions at the end of 2020. EBCC wants Ten years ago, the board of the Euro- vast Eurasian continent. So it is not to ensure that it is available at an af- pean Bird Census Council (EBCC) pro- surprising that the number of species fordable price even in economically weaker countries. EBCC will therefore posed the idea of a new distribution at- endemic to Europe is quite small, with cover part of the production costs for the las to its network of national delegates the exception of the island endemics book. To achieve a price under 100 Eu- at the EBCC conference in Cáceres in the or , or ros, EBCC relies on support in this final (Spain). The first atlas had been pub- the Scops-owl, only recently project phase as well, for example through species sponsorship. Join in and lished in 1997 presenting data most- added to the European species list as support EBBA2: https://www.ebba2. ly collected in the 1980s. The propos- a separate species. Among the more info/support-ebba2/ebba2-species- al was received with enthusiasm. Two widespread endemics are Rock Par- sponsorship/ years of planning, five years of field- tridge, European Herring Gull and Cit- work, collection and evaluation of data, ril Finch. analyses, and finally the production of the book – such a huge project can Distribution hotspots only be managed by a strong team of The first EBCC atlas of 1997 was a hotspots from the Ural Mountains to experts spanning the continent. EBCC milestone for European ornithol- the Caspian Sea, be it in abundance consists of a Europe-wide network of ogy, but data from eastern Europe maps at a resolution of 50 × 50 km institutions and ornithologists. The were scarce and based mostly on ex- or in modelled maps showing occur- decentralised coordination team had pert knowledge and only partially on rence probability at a resolution of members in Sempach, Barcelona and field data. This has changed. Thanks 10 × 10 km. From these maps, Swit- Prague. The number of participants to the huge efforts of all involved, zerland emerges as a hotspot for is impressive: national partners from coverage for EBBA2 was much bet- species like Black Redstart, Rock Par- 48 countries and 120 000 fieldwork- ter in Russia and Turkey than antici- tridge and White-winged Snowfinch, ers, of which 35 000 conducted terri- pated. For the first time, we are able but it clearly lies at the very edge of tory mapping surveys and other sys- to see how European birds are dis- the ranges of Grey-faced Woodpeck- tematic counts. tributed and recognise distribution er or Common Rosefinch.

Abundance (in pairs) not reported 1–9 10–99 100–999 1000–9999

© EBCC

The abundance map for the Rufous-tailed Rock-thrush highlights its strongholds in the southern European mountain ranges. The species has practically disappeared from the Carpathians. Source: European Bird Census Council (EBCC).

32 INTERNATIONAL NEWS

Probability of Change occurrence EBBA1 EBBA1 & EBBA2 – 1 EBBA2 light colours: insufficiently covered – 0

© EBCC The change maps are limited to the area © EBCC already covered in the first atlas. The range The Common Redstart is an abundant breeding bird in the open forests of northern Europe, of the Reed Bunting has shrunk dramatically as the modelled occurrence probability map clearly shows. But the differences north and since the 1980s, especially in southern Europe. south of the Alps are visible as well. Source: European Bird Census Council (EBCC). Source: European Bird Census Council (EBCC).

Winners and losers finding is the northward range shift losers are many species of farmland In any atlas, species expansion is easier in many species, presuma- and steppes such as Ortolan Bunting, to document than range losses, as the bly caused mainly by climate change. Greater Short-toed Lark and Great complete disappearance of a species Eurasian Tree Sparrow and Common Bustard, but also mountain birds like from a grid square is usually preceded Firecrest, for instance, are increasing- Rufous-tailed Rock-thrush and Rock by a population decline. A remarkable ly found in Fennoscandia. Among the Partridge.

Invasive species gain ground Among the 596 species are 57 non-na- tive species, an impressive number, even without including species like the Common Pheasant, whose natu- ral range only just extends into Europe in the region. Many non-na- tive species have significantly expand- ed their range, among them the - ringed Parakeet and other parrot spe- cies and, in southern Europe, some such as Common Waxbill and Red-billed Leiothrix.

The new European breeding bird atlas includes illustrations by 45 artists from 18 countries. Many of them can be purchased, like this picture of a Horned Lark by Jacques Laesser. Further information Part of the proceeds will go towards funding the atlas: https://www.ebba2.info/support- www.ebba2.info ebba2-2/illustrations-for-ebba2/

33 ACKNOWLEDGEMENTS

Decades of commitment

With a friendly «tchack» we say good- hands at the end of 2019 following 30 A heartfelt thank you goes to our bye to Jackdaw authority and Sand years of dedicated work. Katarina Varga collaborators at Biolovision S.à.r.l. for Martin monitor, Christoph Vogel. Ever will take over the monitoring of these their patience and perseverance run- since he compiled the available knowl- two species. We thank Christoph Vogel ning ornitho.ch. We are extremely edge on Jackdaw breeding populations for his decade-long supervision of the grateful to the Federal Office for the in Switzerland in the so-called «white two monitoring schemes and hope he Environment FOEN for its financial sup- book» in the late 1980s, he has re- continues to find joy in observing his fa- port of the monitoring projects. mained loyal to this small member of vourite feathered friends! the crow family. With around 80 vol- Our admiration and thanks go to unteers, he monitored breeding popu- every one of the Ornithological Insti- lations at 160 sites every year. He was tute’s volunteers for their effort and in of the monitoring project for commitment – without their tireless Collared Sand Martins, also supported fieldwork, the monitoring of birds in by dozens of volunteers (see the box), Switzerland would not be possible! We for almost as long. The project concen- are grateful to all our local, regional, na- trated on breeding sites in the cantons tional and international partner organ- of Fribourg, Bern, Solothurn and Aar- isations for the effective collaboration, gau. Christoph will soon be retiring, in particular in the breeding bird surveys and he entrusted his projects to younger and the waterbird census.

The population trends of Eurasian Jackdaw and Collared Sand Martin could only be seamlessly tracked thanks to the dedication of volunteer fieldworkers: Adrian Aebischer, Walter Affolter, Hans Althaus, Hans Peter Althaus, Rolf Amiet, Hans Peter Ammann, Roland Ammann, Walter Amsler, Christof Angst, Christian Bachmann, Samuel Bachmann, Michèle Baechtold, Carl’Antonio Balzari, Jonas Barandun, Annelies Bärenbold, Artur Bärtsch, Sibylle and Daniel Baumann, Michel Beaud, Andres Beck, René Berner, Annette and Stefan Bernhard, Romano Bianchi, Peter Bieli, Hans-Peter Bieri, Monica Biondo, Peter Blaser, Bruno Blöchliger, Jeanine Bolt, Ursula Bolt, Josef Borer, Frank Borleis, Rolf Bösch, Paul Brändli, Laurent Broch, Markus Brüderli, Hans Brüngger, Hans Brunner, Werner Buchser, Reto Buri, Wolfram Bürkli, Paul Burri, Urs Bütikofer, Aquilino Cabezas, Eugen Christ, Ruedi Christen, Walter Christen, Andrea Clavuot, José Collaud, Florian Comment, Alexandre Copertino, Charly Corminboeuf, Carole Daenzer, Susanne Dehler, Verena Döbelin, Catharina Dohrn, Gertrud Donatsch, Jérôme Duplain, Jeannette Dür-Lindt, Annelies Ehrler-Gabathuler, Marc Eichenberger, Regina Eichenberger, Konrad Eigenheer, Verena Ellenberger, Urs Elsenberger, Severin Erni, Maya Fahrni, Karl Fässler, Kuno Feurer, Gregor Fiechter, Olivier Fiechter, Walter Finger, Patrick Fitze, Hansruedi Flück, Laurent Francey, Patrick Frara, Philippe Frei, Otto Freiburghaus, Monika Frey, Daniel Friedli, Jean-Luc Gauchat, Dani Gebauer, Fritz Geissbühler, Lydia and Ruth Gerber, Niklaus Gerber, Rita Gerber, Madeleine Gfeller-Liechti, Paolo Giacometti- Thöni, Erika Giesch, Pascal Grand, Jérôme Gremaud, Leo Grolimund, Marcel Guggisberg-Gerber, Christian Habegger, Theo Haldimann, Gottfried Hallwyler, Nicola Haltiner, Jakob Hartmann, Rolf Hauri, Bernhard Herren, Peter Heuberger, Claudia Hischenhuber, Kaspar Hitz, Susanna Hofer, Sabina Horst, Eva Huber, Niklaus Huber, Otto Hug, Paul Hügli, Christine Hunziker, Gottlieb Hunziker-Lüthy, Leo Hutter, Thomas Imhof, Markus Iseli, Elisabeth Isler, Patrick Jakob, Jacques Jeanmonod, Paul-André Jeanmonod, Norbert Jordan, Adrian Jordi, Willi Jost-Badertscher, Michel Juillard, Elisabeth Kalbermatten, Marianne Käppeli-Habegger, Adrian Keller, Heinz Keller, Regula Keller, Theresia Keller, Andi Kofler, Stefan Kohl, Martin Kohli, Enrica Kohli-Beretta, Jürg Kolb, Markus Krähenbühl, Franz Krauer, Marianne Küffer, David Külling, Felix Kurz, Michael Lanz, Daniel Legler, Daniel Lehner, Barbara Leuenberger Jörg, Martin Leuenberger, Paul Leupp, Annatina Leuthold-Campbell, Werner Löffel, Lilo Looser, Célestin Luisier, Peter Lüps, Benoit Magnin, Hans Märki, Ulrich Marti, Walter Marti, Veronika Martignoli, Roger Maurer, Pius Meier, Sebastian Meyer-Rust, Willi Michel, Lina Minder-Ragettli, Alfred Mischler, Markus Mooser, Max Moser, Paul Mosimann-Kampe, Agi Müller, Claudia Müller, Martin Müller, Hans Murer, Lorenz Mutzner-Käser, Germano Neri, Alain Niclass, Carole Niffenegger, Jean Oberhaensli, Adrian Oser, Benno Oser, Simon-Pierre Parrat, Benjamin Pfäffli, Samuel Progin, Ferdi Proyer, Pascal Rapin, Kurt Räz, Emmanuel Revaz, Lucas Rieder, Gilbert Rochat, Stefan Röllin, Peter Rosin, Attilio Rossi, Olivier Roth, Rolf Ryser, Bea Sager, Marianne Schläpfer-Meyer, Roland Schneeberger, Sylvia Schneeberger, Iris Scholl, Alice Schöni, Ernst Schrag, Harry Schumacher, Eveline Schürmann, Alfred Schwab, Thomas Schwaller, Yvonne Schwarzenbach, Manuel Schweizer, Manuel Scussel, Eva Seiler, Emile Sermet, Otto Sieber, Bruno Siegrist, Walter Siegrist, Ruth Sonder-Augustin, Manfred Steffen, Alex Steiger, Manfred Steiger, Michael Straubhaar, Stephan Strebel, Roger Strozzega, Beat Studer, Erwin Stutz-Bochsler, Maja and Fritz Suter, Alois Tanner, Sergio Tirro, Michael Tobler, Antonio Trippi, Annette Tromp, Pius Tröndle, Martin Tschumper, Brigitte Urech, Ralf Vanscheidt, Stefan Varruch, Christoph Vogel-Baumann, Alois Vogler, Wilfried Vogt-Kalchofner, Gian Voirol, Andreas von Ballmoos, Ernst von Ballmoos, Philippe Vuilleumier, Carole and Samuel Wagner, Res Wagner, Stefan Wassmer, Martin Weggler, Michel Weissbrodt, Fritz Werthmüller, Martin Wettstein, Heinrich Wicki, Yvar Wider, Georg Willi, Robert Winter, Laurenz Wirth, Armin and Margrit Wittmer, Jacques-Louis Wyss, Bruno Zeller, Sibylle Zindel-Grunder, Thomas Zischg, Edith and Rudolf Zulauf.

34 AUTHORS AND COPYRIGHT

The Eurasian Skylark population in Switzerland is in decline. The quality of its habitat has continued to decrease, due mainly to the intensified use of farmland. As a consequence, the Skylark is now considered Vulnerable and has been added to the new Red List of breeding birds published this year by the Federal Office for the Environment FOEN.

Authors and copyright

Authors Peter Knaus, Thomas Sattler, Hans Schmid, Nicolas Strebel, Bernard Volet With the collaboration of Sylvain Antoniazza, Marcel Burkhardt, Lukas Jenni, Isabelle Kaiser, Verena Keller, Marc Kéry, Gilberto Pasinelli, Arno Schneider, Martin Spiess, Samuel Wechsler Translation Stephanie Morris Images Front cover: Red Kite: M. Burkhardt; p. 2: Grey Partridge: B. Rüegger, Common Little Bittern, Boreal Owl, Eurasian Jackdaw: M. Burkhardt; p. 3 Mallard, White- winged Snowfinch: M. Burkhardt, Reed Bunting: D. Occhiato; p. 4: Cornelis Neet: Direction générale de l’environnement du canton de Vaud; Red-backed Shrike: M. Burkhardt; p. 5: Grey-faced Woodpecker: R. Martin; p. 6: Grey Partridge: Richard Brooks (rspb-images.com); p. 7: Meadow Pipit, White Wagtail: M. Burkhardt; p. 8: Boreal Owl: R. Kistowski; p. 10: Rook: M. Schäf; p. 11: Eurasian Jackdaw: M. Burkhardt; p. 13: European Turtle-dove: M. Burkhardt; p. 16: Collared Flycatcher: R. Martin, Wood Warbler: A. Wullschleger; p. 17: Eurasian Jay: M. Varesvuo; p. 18: Common Crane: B. Rüegger; p. 21: Red-crested Po- chard: R. Martin; p. 22: Red Kite: A. Aebischer; p. 23: two images of Red Kite: A. Aebischer; p. 24: Mallard: D. Occhiato; p. 25: Eurasian Wigeon: M. Schäf; p. 26: Black-headed Gull: R. Martin: p. 27: Black-headed Gull: M. Burkhardt, Black-headed Gulls with tractor: M. Varesvuo; p. 29: Great White Egret: R. Mar- tin; p. 30: landscape Spain: A. M. Domínguez, Northern Wheatear: M. Burkhardt; p. 31: Common Redshank: M. Burkhardt; p. 32: Rufous-tailed Rock-thrush: D. Occhiato; p. 33: Common Redstart: R. Aeschlimann, Reed Bunting: M. Burkhardt, Horned Lark: J. Laesser; p. 35: Eurasian Skylark: R. Kistowski. Maps on p. 17–18: copyright www.eurobirdportal.org. Maps on pp. 32–33: copyright European Bird Census Council (EBCC). The copyright for the map background (relief maps) is held by the ETH Zurich Institute of Cartography and Geoinformation. Other images: archive of the Swiss Ornithological Institute. ISSN 2297-5691 (electronic resource: 2297-5705) Recommended citation Knaus, P., T. Sattler, H. Schmid, N. Strebel & B. Volet (2020): The State of Birds in Switzerland: Report 2020. Swiss Ornithological Institute, Sempach. PDF-download www.vogelwarte.ch/state

© 2020, Swiss Ornithological Institute

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